China is now inviting international tourists into a secret underground nuclear plant for the first time ever. Billed as ‘the world’s largest man-made cave,’ the former 816 Nuclear Military Plant in the suburban Chongqing district has been remade into a tourist attraction, where visitors descend far underground to learn about Cold War nuclear weapons. With neon lights and spooky echoes from its nuclear past, the underground bunker offers a unique and unforgettable experience for travelers in what is most certainly southwest China’s coolest cave.

The nuclear plant was originally designed to manufacture plutonium in the 1960s, part of a military megaproject that lasted 17 years and involved some 60,000 soldiers. The site was a massive secret, encompassing one million square feet of underground structure. The plant halted operations in 1984 and was officially declassified in 2002. The government opened it briefly for local tours in 2010 before shuttering it once more. It had not been open to the public again until early October, when the plant’s winding man-made caves were outfitted with elaborate light displays, a move designed to target foreign tourists for the first time.

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Reportedly, the expansive underground plant includes 18 caves and 130 tunnel roads, but only one-third or so of the total square footage is open to public tours. One part of the former nuclear plant now acts as something of a museum to its former purpose, with a 100-foot-tall hall where images of atomic weapons and plutonium processing are projected onto neon movie screens.

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Each room of the underground bunker highlights nuclear weapons in some way, with the added creep-factor of eerie blue and red lights that would look more at home in a nightclub than a former military site. Still, the public seems eager to sign up for one of the two-hour tours being led through the once top secret project. Could China’s latest tourist attraction spark a new trend in ‘nuclear spelunking’?

Via CNN

Images via China Daily